2d sprite bone rigging
To get started with your project you could enable the addon Import Images as Planes in Menu: File / User Preferences.

It will be accessible from the menu File / Import / Image as Plane and create a plane an UVMap and assigns the image texture. 
Note: You need to set the Viewport Shading to texture otherwise you won't see the image texture.



Bones are used to deform geometry you should ask another question (perhaps add an illustration) on what exactly you want to achieve.



You can tweak the subdivided edges in the UV-Editor and scale to maintain the proportions. Separating P By Selection for e.g. the legs allows you to have single objects for this part of the image which can be animated using bones as shown in the image above.